import Vue from 'vue'
import VueRouter from 'vue-router'
import Login from '../components/Login.vue'
import Home from '../components/Home.vue'
import Welcome from '../components/Welcome.vue'
import Users from '../components/Users.vue'

Vue.use(VueRouter)
/* const routes = [] */
const router = new VueRouter({
  routes: [
    { path: '/', redirect: '/login' },
    { path: '/login', component: Login },
    { 
      path: '/home', component: Home, redirect: '/welcome', 
      children: [
        { path: '/welcome', component: Welcome }, 
        { path: '/users', component: Users }] }
  ]
})
/* 挂载路由导航守卫--如果用户通过地址直接访问后台，验证token是否存在--判断用户是否偷渡--存在放行 不存在跳转到登录界面 */
/* to 将要访问的路径 from 从那个路径跳转而来， next()放行 next("/login") 强制跳转 */
router.beforeEach((to, from, next) => {
  if (to.path === '/login') return next()
  const tokenStr = window.sessionStorage.getItem('token')
  if (!tokenStr) return next('/login')
  next()
})
export default router
